BRPI0902385A2 - bearing segment and bearing for vehicle internal combustion engines - Google Patents

Abstract

BEARING BRONZINE AND SEGMENT FOR VEHICLE INTERNAL COMBUSTION ENGINES; The present invention relates to a bearing bearing segment (100) for internal combustion engines, composed of a body (C) defining an internal surface (1) that receives a coating and makes contact with a layer of oil film lubricant and an external surface (2), opposite, associated with a bearing, the internal surface (1) being provided with at least one first area (10) substantially free of the compression load resulting from the movement of the piston by the explosion of air mixture fuel and a second area (20) that receives compression load from the movement of the piston by the explosion of air-fuel mixture, the first area (10) having at least one surface portion (3) to capture foreign particles present in the fuel layer. lubricating oil film, the surface portion (3) comprising a plurality of cavities (4) positioned so as to enable at least one foreign particle to be captured and retained p or at least one of the cavities (4) while moving in the direction of the lubricating oil flow, before reaching the second area (20).

Description

Patent Descriptive Report for "BEARING SEGMENT AND BRONZINE FOR INTERNAL VEHICLE COMBUSTION ENGINES".

The present invention relates to a demancai segment intended for use in internal combustion engines comprising, in a region which receives no compressive load from the explosion movement of pistons, cavities or holes capable of captivate particles or debris carried by the lubricating oil. The present invention also relates to a two-segment bearing, where at least one of them has the innovative characteristics described and defined.

Description of the prior art

Piston internal combustion engines essentially comprise an engine block (comprising one or more cylinders and crankshaft assembly or crankshaft assembly) to which one or more cylinder heads are associated. The crankshaft assembly is made up of pistons, connecting rods and crankshaft.

The connecting rod is the part that connects the piston to the crankshaft and has the primary function of converting the alternate rectilinear movement of the piston inside the cylinder into a continuous angular movement of the crankshaft. The connecting rod is basically composed of the head (the widest part), body and foot, the head being fixed to the crankshaft by screws, and the foot (the opposite end of the workpiece) fixed below the piston by the bolt. . Some connecting rods have an oblique connecting head, making it easy to access during engine assembly and disassembly.

During engine operation, the piston (s) move linearly and reciprocally. Solidarity with each piston, the connecting rod moves and its head, associated with the crankshaft, describes a circular motion, causing angular movement of the crankshaft.

To enable the engine to function properly, it is necessary that the contact between the crankshaft and the other engine components be carried out by means of bearings known to those skilled in the art as bearings or bushings. Whatever their specific configuration, however, they are generally known as sliding bearings.

In a piston internal combustion engine, bearings or bushings may be used (i) as crankshaft shaft bearings in relation to the engine block, (ii) as piston rod bearings in relation to the axle shaft and (iii) as camshaft bearings. valves, among other less common applications.

Specifically, bearings developed for use in new crankshafts are called bearings. In general, the bearings are formed by two semi-circular steel housings (to facilitate assembly), internally coated with soft metal, with properties to reduce friction and embedding of foreign particles.

The outer surface of a bearing has such hardness characteristics that it allows a solid contact with its housing, without deformation, ensuring its correct support and providing the correct dissipation of the heat generated by friction (friction), thus avoiding overheating.

Already the inner surface of the bearings has a coating that can be composed of various metal alloys, such as copper or aluminum alloys, among others, always seeking resistance to abrasion and wear and good deformability, providing long service life even under the more severe engine operating conditions.

Reduction of friction in internal combustion engines is an important aspect to be pursued, as increasingly low-displacement, energy-efficient objective-semotors increase the specific power produced and overload their internal components with greater intensity. , which need to be designed to support these efforts.

In addition, the topography and internal surface profile of bronzines has also become an increasingly important aspect for improving system performance. In this regard, a number of special bearing finishing techniques have been used to achieve coatings that maximize reduced friction properties, good lubricity and high durability.

One of the weaknesses of conventional bearings is that their inner lining can be damaged (scratched) by foreign bodies carried by the lubricating oil due to the high acting forces therein. Since there is no cavity or recess as well as no means for such particles to be rapidly expelled, the durability of the part can be considerably reduced if, for example, the lubricant oil change is too much delayed.

In order to remedy this inconvenience, a series of bearings have been proposed, provided with slots or holes distributed along the region receiving compression load from the piston boom movement. These grooves have the function of directing foreign particles contained in the lubricating oil out of the bearing, preventing damage or defects to the inner surface of the bearing, which, in extreme conditions, could cause premature failure.

Japanese Patent Document JP 5-202936 discloses a hydrodynamically bearing bracket for use in internal combustion engines, which is nonetheless comprised of an overload operating portion and its adjacent opposite portions which do not operate under load.

Adjacent to the exit region and an unloaded region, the bearing comprises a plurality of grooves for removing foreign particles present in the lubricating oil. The document further describes that the depth of such grooves decreases toward the portion that operates under load.

However, the solution proposed by this document is not effective, since instead of retaining the foreign particle by removing it from the lubricating oil, it merely drives it out of the bearing. Thus, nothing prevents the same particle, if not retained by the lube filter, from returning to the bearing or hitting another engine component and possibly damaging it. Another drawback of the solution proposed in this document is that grooves in the workpiece cause an increase in the oil flow supplied by the pump so that the hydrodynamic bearing condition of the bearing is possible. Higher flow leads to higher power required by the oil pump, which needs to be absorbed from engine operation, reducing the power available for use.

US Patent Document US 2008/0187259 relates to a bearing bearing for use in internal combustion engines, the inner surface of which comprises two end-axial recesses, located adjacent the outlet area and interconnected with a recess. that receives oil from the pump.

Due to the specific constitution of this bearing, any foreign particle present in the oil tends, with the rotation of the bearing in relation to the bearing, to enter the radial recess and to be led to one of the extremity recesses, through which it leaves the inner surface of the bearing.

As in the previous document, the solution presented is not very effective, as instead of retaining the foreign particle by removing it from the lubricating oil, it only leads out of the bearing and returns it to the oil lubricant. In addition, the bearing described in this US document also forces an increase in the flow of oil supplied by the pump to make the hydrodynamic sustaining situation of the bearing possible. Increasing the power required for oil pump operation.

Throughout the foregoing, it is noted that a bearing bearing for use in internal combustion engines has not yet been developed to capture and retain foreign particles of lubricating oil, preventing damage or defects to the inner surface of the bearing, which do not bring disadvantages. such as increasing the power absorbed by the oil pump and having a commercially viable manufacturing cost.

Objectives of the Invention

The aim of the present invention is to provide a bearing bearing segment for use in internal combustion engines having an internal surface formed with cavities capable of capturing foreign particles or lubricant-laden debris in a region that is not loaded with substantial compression from the explosion of air-fuel mixture.

Furthermore, the present invention relates to a mancaique bearing comprising at least one objectified segment.

Brief Description of the Invention

The objectives of the present invention are achieved by a bearing segment for internal combustion engines composed of a body defining an inner surface which is coated and in contact with a lubricating oil film layer and an opposite, associable outer surface. to a bearing, the inner surface being provided with at least a first area substantially free of the compressive load from the movement of the piston by the blast of air-fuel mixture and a second area receiving compression load from the movement of the piston by the explosion of air-fuel mixture, the first area having at least one surface portion for capturing foreign particles present in the lubricating oil film layer, the surface aporion comprising a plurality of cavities positioned to enable at least one foreign particle to be capped and retained by at least one of the adhesion while moving the direction of the lubricating oil flow before reaching the second area.

Also, the objects of the present invention are achieved by a bearing comprising at least one segment as defined above.

The above-mentioned features, in addition to other aspects of the present invention, will be better understood by way of the examples and detailed description of the following figures.

Brief Description of the Drawings

The present invention will hereinafter be described in more detail based on an exemplary embodiment shown in the drawings. Asfiguras show: Figure 1 - is a perspective view of a demancai segment representative of the state of the art.

Figure 2 is a perspective view of the object-bearing bearing segment of the present invention.

Figure 3 is a plan view of the bearing bearing segment shown in Figure 2.

Figure 4 is a side view of the bearing segment shown in Figures 2 and 3.

Figure 5 is a schematic illustration of the surface portion of the bronzine segment object of the present invention in which the cavities for trapping and retaining particles present in the lubricating oil are positioned.

Figure 6 is a perspective illustration of the detail of the cavities shown schematically in Figure 5.

Figure 7 - is a micrograph of the surface of the cavities increased 100 times.

Figure 8 is a micrograph of a section of the demancai bronzin segment in the surface region of the cavities, illustrating them.

Detailed Description of the Figures

Figure 1 illustrates a half, or segment, of a prior art hydrodynamic demand bearing bearing 50 for use in prior art internal combustion engines having an internal surface divided into a portion 51 operating under load (under compressive stresses). flow rates of the air-fuel mixture explosion and corresponding piston movement) and respective opposing adjacent portions 52.53 which do not operate under load and which are located adjacent to the outlet region (free ends of the bearing).

In portions 52.53, bearing bearing 50 comprises a plurality of substantially transverse, or axial, grooves 54-57 for removal of foreign particles present in the oil. The depth of such scratches decreases towards the portion operating under load 51.

However, such a solution is not as efficient as the grooves 54-57 only direct foreign particles out of dabronzine without capturing them. Thus, such particles return to the lubricating oil, so it cannot be guaranteed that they will not return to the oil film that lubricates the bearing or any other engine component.

Another drawback related to the prior art bearing illustrated in Figure 1 is the excessive volume of the grooves 54-57, which require a high amount of lubricating oil to fill and enable the correct hydrodynamic bearing effect, avoiding metal-metal contact. rotating shaft with the bearing.

This large amount of oil required to ensure hydrodynamic bearing effect results in a large capacity / flow oil pump, which has the drawbacks of increased engine power consumption and, at least in theory, an increase in engine power. in the oil pressure sent to the other parts of the engine, such as the high parts (cylinder head and valve train).

As a general rule, the increase in oil pressure needs to be correctly equated because, as is well known by those of skill in the art, some engine components such as hydraulic valve caps may be impaired in situations of excessive oil pressure.

Figure 2 illustrates the hydrodynamically bearing segment 100 of the present invention, provided with a substantially semicircular shaped body C defining a first inner surface 1 and a second outer surface 2. The inner surface 1 is provided any coating that provides abrasion and wear resistance and good formability, providing long service life even under the toughest operating conditions of the engine.

The inner surface 1 further has at least one surface portion 3 provided with a plurality of cavities 4, the function of which will be explained below. The outer surface 2 may be made of any metal material, necessary or desirable. Similarly, the coating of the inner surface 1 may vary considerably without the resultant invention no longer falling within the scope of protection of the appended claims.

The inner surface 1 is that which makes contact with the lubricating oil film when segment 100 is assembled and in operation, whereas the outer surface 2 is that facing the static bearing properly, such as the bearing present on the motorno block if of a crankshaft shaft.

The bearing is formed by two segments 100 positioned opposite each other oppositely to define a circular opening for positioning. In the case of the bearing object of the present invention, at least one of the segments must have the aforementioned plurality of cavities 4. Segment 100 has an axial length measurement illustrated in Figure 3 with the number 101.

Based on Figure 4, the bronzine segment 100 can be hypothetically divided into three main parts, a first part (shown as 10) adjacent to a first free end of the segment, a second substantially intermediate part 20 and a third portion 30 adjacent to a second free end of segment 100.

Simply put, it can be said that the first part 10 extends about 45 degrees from the first free end of segment L1, the second part 20 extends for the 90 consecutive degrees, and finally the third Part 30 extends through the final 45 degrees to the second free end L2 of the segment. Of course, there may be numerous variations without the resulting invention ceasing to be included in the scope of protection of the claims.

Preferably, the second portion 20 of the segment, which is positioned substantially centered, is subjected to o-driven loading by the movement of the piston upon explosion of the air-fuel mixture (thus being a charged portion). Parts 10 and 30, therefore, correspond to the regions of segment 100 that are not stressed from the explosion of the air-fuel mixture (uncharged parts).

Still as can be seen from the analysis of figures 3 and 4, the surface portion 3 provided with the plurality of cavities 4 is positioned in the first area 10 of the segment, that is, in an uncharged region, which is an indispensable condition. for the proper operation of the invention as will be described below.

Of course, the positioning of the loading portion of the bearing may vary freely. In some engines, especially those that operate according to the diesel cycle, the positioning of the debronzine segment in the connecting rod is inclined. In such an arrangement, the area of the segment where the stresses arising from the blast of the air-fuel mixture do not focus on the central portion but adjacent to one end. Thus, in the case of a bearing segment object of the present invention designed for operation in a motor thus configured, the surface portion 3 provided with the plurality of cavities 4 would be positioned in a region where there was no loading, which would possibly be different from the region. of the segment illustrated in figure 4.

Essentially, the positioning of the surface portion 3 provided with the plurality of cavities 4 may vary freely in the segment as long as it is positioned outside the charged region and a particularity regarding the oil flow is observed, which will be described below. .

Preferably, the surface portion 3 is positioned at an angle α which, depending on the characteristics of the motor, may vary from 10 to 60 degrees starting from the center of the segment (preferably 45 degrees) and the end of the surface portion 3 is positioned at an angle β from angle α which can be from 1 to 30 degrees (preferably 15 degrees ")

Even more preferably, the surface portion 3 has a given width 102 and extends over the entire axial length 101 of the bronze segment 100, as can clearly be seen from Figure 3. However, a segment 100 can be designed according to the teachings. of the present invention and included within the scope of the claims, wherein the surface portion 3 has an axial length less than the axial length 101 of the segment.

It is important to note that whatever the preferred position of the cavity-provided surface portion 4, it should be positioned adjacent to the pressurized oil feed and prior to the loading region, considering the lubricant flow in segment 100.

When an axis rotates within the cavity substantially formed by the two bearing segments, it naturally drags lubricating oil in the direction of its rotation. The oil therein is constantly fed under pressure by the pump so that the hydrodynamic bearing of the axle occurs, that is, so that the axle is sustained in the oil without touching the bearing segments (which would cause severe component wear).

In order to optimize system operation, segment 100 is designed such that the lubricating oil is fed adjacent to the first free end L1 and moved longitudinally across its inner surface to leave the bronzine segment at the second free end L2.

Of course, to optimize lubrication conditions, shaft rotation is such that it rotates in direction 44 from L1 to L2, following the inner surface of segment 100 and allowing the flow of lubricating oil together with the pump (see figures 3 and 5).

Considering the flow of lubricating oil, the surface portion provided with cavities 4 should be positioned in an uncharged region and substantially adjacent to the location where oil is fed into segment 100 to allow any metallic particles to pass through before reaching it. the charged region of the bronzin.

In this regard, it is well known to those skilled in the art that when a foreign particle that reaches the debronzine segment via lubricating oil and is exposed to the high compressive forces in the charged region, there may be (and indeed occurs in many cases) an ingestion of this. particle, which adheres permanently to the internal surface. Over time, any foreign particles embedded in the inner surface of the segment can lead the bearing to premature fatigue or sticking as well as scratch the shaft. Such a situation is more serious the greater the negligence in the oil change interval and / or the use severity to which the engine is subjected.

Therefore, the bronzin segment 100 comprises the allusion with cavities 4 positioned adjacent to the surface oil feed and, always thinking in the direction of oil flow, prior to the charged region.

Thus, in the segment 100 object of the present invention, the oil film reaches the inner surface and flows both by the pressure exerted by the pump and the circular movement of the shaft. On its way, the oil crosses the cavity portion 4 before reaching the charged region and any particles are 'captured' by the cavities 4, thus preventing them from reaching the charged region and eventually sticking to the inner surface. segment in the loaded region. The positioning of the cavities is such that the pressure in the oil film at that location is sufficient to assist in trapping particles through the cavities.

Thus, the present invention ensures that the particles will not circulate again in the lubricating oil, preventing them from eventually reaching this or other points of the engine and somewhat shortening their service life.

In order to facilitate particle capture and adhesion, cavities may take various shapes. Preferably, the cavities 4 are produced by the Laser Surface Texturing (LST) process 1 but may be made by another process as long as they achieve the same final result.

Figure 5 shows the surface portion 3 provided with cavities 4 at a given distance from each other (see number 43) and also the direction of rotation of axis 44 (and hence the oil flow) through segment 100. The cavities 4 are positioned such that when a foreign particle moves in the direction of the lubricating oil flow, it encounters at least one cavity 4 capable of capturing and retaining it, whatever its path (whether perfectly straight or oblique).

Preferably, and as can be seen in Figure 6, the cavities 4 have a diameter 41 of 10 to 300 μπ \ (typically 100 μίτι), depth 42 of 10 to 200 μίτι, (typically 50 μιτι), and a distance of between 10 and 300 μπ. between centers 43 comprised between 20 and 500 μηι, usually 200 μηι. With these characteristics and arrangement, greater efficiency in the capture of foreign particles from the oil film is ensured. However, efficient results can also be achieved with other characteristics.

Moreover, the cavities are not required to be equidistant with each other.

The positioning of the cavity portion 4, combined with diameter 41 and cavity distribution, makes it possible for a strange particle to be between the bearing and the axis of rotation in the direction of axis 44 and the oil flow to traverse it. find at least one cavity 4 and consequently this particle can become trapped, preventing it from continuing its movement to the charged region.

By catching any foreign particles, segment 100 prevents surface damage or, in extreme circumstances, premature failure.

It is evident, however, that the cavities may be of any other shape and / or may be positioned in any other way, equidistant from one another or not, as long as efficient results are obtained.

It is further noted that a two-segment bearing, where at least one of them has the innovative characteristics of the defined segment 100, is a new and inventive invention and is within the scope of the appended claims.

Having described an exemplary preferred embodiment, it should be understood that the scope of the present invention encompasses other possible variations and is limited only by the content of the appended claims, including the possible equivalents thereof.

Claims (10)

1. Inner bearing segment (100) for internal combustion engines, consisting of a body (C) defining an inner surface (1) which is coated and contacts a defilm layer of lubricating oil and an outer surface ( 2), opposite, associated with a bearing, the inner surface (1) having at least one first area (10) substantially free of the compressive load arising from the movement of the piston by the explosion of air-fuel mixture and a The second area (20) which receives compression loading from the movement of the piston by the blast of air-fuel mixture, the first area (10) having at least a surface portion (3) for capturing foreign particles present in the layer of lubricating oil, the segment (100) being characterized by the fact that the surface portion (3) comprises a plurality of cavities (4) positioned to enable at least one foreign particle to be capped. retained and retained by at least one of the wells (4) while moving in the direction of oil lubricant flow before reaching the second area (20). Bronzine segment according to claim 1, characterized in that the distance (43) between the centers (c) of the cavities (4) is between 20 and 500 μητι. Bronzine segment according to claim 1, characterized in that the cavities (4) have a distance (43) between the centers of 200 μιη. A brazing segment according to claim 1, characterized in that it further comprises a third area (30) also substantially free of the compression load arising from piston movement by the explosion of air-fuel mixture. Bronzine segment according to claim 1, characterized in that the surface portion (3) extends throughout the axial length (101). A bearing segment according to claim 1 or 2, characterized in that the surface portion (3) is positioned at an angle α ranging from 10 to 60 degrees from the center. Bronzine segment according to claim 6, characterized in that the end of the surface portion (3) is positioned at an angle β from angle a, which may be from 1 to 30 degrees. Bronzin segment according to Claim 1, characterized in that the cavities (4) have a diameter (41) of between 10 and 300 μητι. A bearing segment according to claim 1 or 8, characterized in that the cavities (4) have a depth (42) of between 10 and 200 μηι. Bronzine, characterized in that it comprises at least one segment (100) as defined in claims 1 to 9.